1. Field of the Invention
The present invention relates to a device for preventing torque peaks generated by an internal combustion engine in a motor vehicle from being introduced into its drive train which is connectable with the internal combustion engine via a friction clutch acting on a flywheel mass. The friction clutch is arranged in a housing which is connectable with the flywheel mass so as to be fixed with respect to rotation relative thereto and the friction clutch has a pressing plate which is acted upon by a spring.
2. Description of the Related Art
A torque transmitting device is known, for example, from the German Utility Model G 84 10 765.0.
In connection with a two-mass flywheel, a slip clutch within a torque transmission device is known, for example, from DE 44 20 934 A1. Torque peaks or torque shocks are generated by the rough running of an internal combustion engine. In the known device, excessive torque shocks are prevented from being passed on to the subsequent drive train by a slip clutch positioned between the secondary flywheel mass and the carrier plate. The secondary flywheel mass is pressed against the carrier plate by two spring forces. The first of the two spring forces is via plate spring which acts on the friction facings of a pressing plate which are pressed onto the flywheel mass when the clutch is closed. The pressing plate is loaded axially by the plate spring. The second of the two spring forces is via a wave spring which is inserted between the clutch housing and the secondary mass. The torque transmission is effected on one side from the carrier plate connected with the crankshaft, through the secondary mass, the friction facings, and the pressing plate. On the other side, the torque transmission is effected through the carrier plate, the secondary mass, the wave spring, and the clutch housing. The torque transmission capability of this slip clutch is determined by the spring rates of the plate spring and of the wave spring and by appropriate choice of friction pairings at the friction faces. Since the secondary flywheel mass and the clutch are only connected with the carrier plate by a frictional engagement, a relative rotation of these parts occurs relative to the primary flywheel mass if the torque is too high.
The extreme torques occurring during a change of load and in the resonant range are prevented from resulting in the destruction of the two-mass flywheel, clutch disk or other structural component parts of the drive train because of this relative rotation capability.
A problem with this known construction is that it is quite cumbersome to assemble. A large number of structural component parts is needed to maintain the double frictional engagement. In addition, corresponding to the high logistical effort required to assemble these devices, the assembly costs are high. Also, the overall unit comprising the flywheel and clutch is correspondingly large in the axial direction due to the large number of structural component parts. Due to increasing vehicle optimization demand accompanied by a simultaneous increase in the multiplicity of equipment in vehicles, the available space in the engine compartment continuously decreases. For this reason, all structural component parts are required to be as compact as possible.
Proceeding from this set of problems, the generic device is to be improved in such a way that it requires fewer structural component parts, has a compact construction and is simple and economical to assemble.